Expanding chains for wrist bands



Aug. 21, 1956 A. PINSON 2,759,325

EXPANDING CHAINS FOR WRIST BANDS Filed April 13, 1953 INVENTOR.

United States Patent EXPANDING CHAINS FOR WRIST BAND'S Alfred Pinson,Stamford, Comm, assignor to Apex Accessories Co., Inc., Greenwich, Conn.

Application April 13, 1953, Serial No. 348,193

1 Claim. (Cl. 5979) My invention relates to chains suitable for wristbands and the like and it is characterized by spring actuated jointedparallelograms normally retracting a string of blocks.

An object of the invention is to provide an expanding chain in which thespring actuated jointed parallelograms are pivotally coupled to theblocks to obtain a maximum of extensibility of the chain.

Another object of the invention is to provide an expanding chain inwhich the spring actuated jointed parallelograms permit the use ofcircular or polygonal contour of the sides and the upper face of theblocks forming the chain.

A further object of the invention is to provide an expanding chain inwhich the blocks move angularly as they move linearly.

In the appended drawing Figure 1 is a top view of a fragment of thechain embodying my invention shown in retracted position.

Figure 2 is an enlarged top view of the chain extended, with the coversremoved from the upper elements of the chain;

Figure 3 is a section on line 33 of Figure 2;

Figure 4 is a section on line 4-4 of Figure 2;

Figure 5 is a side elevation of a chain fragment in the retractedposition; and

Figures 6 and 7 are a diagrammatic top view of the polygonal contourchain in extended and retracted position respectively.

Referring to the drawing, 10 are the liners forming the bases of the rowof blocks Each liner is provided with two openings 11 of which one isshown disengaged in Fig. 2.

The said openings are diametrically opposite and are located on oppositesides of the longitudinal axis of the chain. A line joining saidopenings, cuts the axis at an acute angle. A bottom link 12 is pivotallysecured with one end thereof to a corresponding opening 11 by a pivot13. To the same pivot 13 a side link 14 is also secured pivotally withone end thereof; so that hnks 12 and 14 can move angularly with respectto one another and with respect. to the liner they are connected with.

The portion 15 of the side link 14 is off-set to engage the uppersurface of the liner 10 bringing the major portion 16 of side link 14into plane of liner 10. The portion 16 extends toward a proximate liner10 where at, the end of portion 16 is pivotally connected by a tubularpivot 17 to the end of a bottom link 12. The bottom link 12 extends fromthe proximate liner and forms part of a jointed parallelogram pivotallyconnecting proximate liners.

Each jointed parallelogram is formed of two opposlte bottom links 12 andtwo opposite side links 14 and is connected pivotally to proximateliners 10 through the respective pivots 13 of a jointed parallelogram(see Fig. 2). The tubular pivot 17 which connects only the end of bottomlinks 12 with the end of side links 14 ice houses a helical spring 18.One end 19 of said spring 18 engages a hook 20 preferably forming anintegral part of side link 14. The other end 21 of the spring 18 abutsthe side of a cover 22 for the bottom link 12. The springs in eachparallelogram are tensioned to draw the string of liners to retract thechain.

When the chain is extended (see Fig. 2) from normal (retracted) position(see Fig. 1) the bottom links 12 are moved from the position indicatedin dotted lines in Figure l to that shown in full lines in Fig. 2. Theside links 14 swing about the curved portion 23 of the liner 10 as thechain is extended. To prevent an undue strain on the springs 18 the kneeportion 24 at the junction of portion 15 and 16 of side links 14 is madeto travel in a notch 25 in the edge of the liner 10.

As the liners 10 are pulled to extend the chain against the resistanceof springs 18 the angles of the jointed parallelograms between theliners change at the juncture of the bottom and side links. The bottomand side links move angularly on their pivots 13 and 17 of eachparallelogram imparting in turn an angular movement to liners connectedthrough pivots 13 thereto. The angular movement of the liners increasesspacing between the liners by the movement of the pivots 13 toward thelongitudinal axis of the chain, indicated in dot and dash lines in Figs.1, 2, 6 and 7. The reverse takes place when the springs 18 retract thechain. It is therefore evident that the liners connected as described bythe jointed parallelograms will move angularly when they are movedlinearly along the axis of the chain.

Each liner is provided with seats 26 to accommodate tabs (not shown)extending from a cover 27, to be locked to the liner 6. Said cover 27 isprovided with cut outs 28 in the side thereof, to permit the movement ofside links 14 (see Figs. 34). Each link 14 is also provided with a cover29 extending only over the portion 16 of the link 14. The means forlocking the covers 22 and 29 to the respective links 12 and 14 have beenomitted.

In Figs. 6 and 7 the bottom links 30 are substantially identical inshape to bottom links 12 shown in Figs. 1 to 5 inclusive. The liners 31(see Fig. 6) are shown to be polygonal and so are the side links 32. Inthe retracted position of the chain (Fig. 7) the covers 33 for theliners 31 are of same or similar polygonal shape and the cover 34 forthe side links are of a shape to conform to proximate contour of thecover for the liner.

In extended position of the chain (see Fig, 6) the angular displacementof the liners is more apparent than in Fig. 2 because of the shape, Italso shows that the apparent continuity of contact between liner 10 andside links 14 is not present when the contours of liner and side linksof the chain are polygonal in contour. The performance of either chainis same provided the length of the bottom link clears the peripheralhigh points of the liners cover by the side links cover.

The means for preventing undue strain on springs 18 are the knee 24 oflinks 14 and notches 25 in the edges of the liners 10. This means inaddition limits relative angular movement between the liners 10 and sidelinks 14. It will be noted that the diagonals of the jointedparallelograms cross the longitudinal axis of the chain at an acuteangle in normal retracted position of the chain and the acuteness ofsaid angles increases with the extension of the chain. It will also benoted from Figs. 1, 2 and 3 that the acute angles at no time arepermitted to become either zero or this being prevented by theengagement of the notches 25 in the edge of the liner 10 with thecorresponding offset or knee portion 24 in the side links 14 when thechain is ex-- tended. The shape and form of the chain in retractedposition depends on the nesting of the complimentary lateral contours ofthe liners and side lin'k thereat, as it is shown in Figs. 1 and 2 and 6and 7. In the normal retracted position of the chain a pair of oppositelinks of the jointed parallelograms have a major part thereof under the,proximate liners which are-closelyspaced and the vother ,pair-of linksof the parallelogramnesting on the ,sideof :the proximate liners. Inthezextended position =of'the chain the jointed ,parallelograms havemajor parts of the links thereof between the proximate liners.

I claim:

ln-an-expanding chain, a string of-closely spaced liners in theretracted position of the chain, each liner having a pair of spacedopenings adapted to be 'disposed on opposite sides of the longitudinalaxis .of .the chain, the

proximate openings of adjacent liner being also adapted to be onopposite sides of said axis, each of said liners having 'a,predeterminate lateral contour, a pair of side links each adapted to heconnected pivotally with one end thereof to a corresponding opening ofthe liner on thetop thereof, a-pair of bottom links one for each sidelink adapted to be connected ,pivotally with one end thereof at thebottom of the liner to a corresponding pivot of side link, the other endof a bottom link being adapted to be ,pivotally coupled :to the otherend of a sidelink of a proximate liner, said top and'bottom'lin'ksforming a jointed parallelogram between adjacent liners when the chainis extended, a spring associated with the pivotal coupling of saidbottom and side links to normally move the links to closely space theliners, each of the side links having an offset to bring the major partof same into the plane of the liner, said major part of the link havinga lateral contour complimentary to that portion of the contour of theliner it is adapted to face in the-closely spaced position of theliners, said liner having notches for corresponding ofisets of the sidelink to limitthe angular movements between the side links and liner itis coupled with, to limit the extension of the 'chainto prevent unduestrain on the springs.

References Cited in the file of this patent UNITED STATES PATENTS2,117,395 Bigney May 17, 1938 695,493 Pinson Nov. 30, 1954 FOREIGNPATENTS 7,581 Great Britain Mar. 29, 1902 628,966 France Nov. 2, 1927

